Gauged Nut Slotting Files

About This Item

Each chrome-alloy steel file has twin 4" cutting edges. Among our most popular tools, these professional files help you get the job done quickly and correctly.

What files do I need?Choose nut slotting files that are the same size or no more than a few thousandths larger than your individual string gauges. A smaller file can also be rocked side to side to widen a slot to the desired size. For example, you can cut a .043" slot with a .042" file by moving it around a bit.

Save 10% by purchasing the complete set
Always have the right gauge for cutting and shaping string slots on any instrument. Complete set of nineteen files includes every size we offer.

Tip: Slotting Tune-o-matic style saddlesNut slotting files work great for metal saddles. Choose your file size as you would when slotting a nut: use the same gauge as the string, or a few thousandths larger. After filing to the desired depth, we suggest polishing the slot with Mitchell's Abrasive Cord to remove file marks and burrs.

Nut slotting files

Sadly, Stew-Mac's quality on these hasn't improved one whit since I last tried them. The shape of the cutting edge is nowhere near hemispherical - not even rounded.

Not recommended.

Response from StewMac

Thank you for your feedback on these files. If you are not happy with your purchase, we would be happy to take them back for a refund or store credit. You can give us a call or use the "Contact Us" link on our website. We have a 100% satisfaction guarantee and we stand behind our tools and parts.

Pretty Good Files

These are OK files if it's all you can afford and they are on sale. They do cut nice and smooth. But I am not a fan of OK tools. If you want to do quality work, buy the best. The means you want the 45XX series double edge tapered files. Those cost three times more but are ten times better.

Gauged Nut Slotting Files

I have been using these files for a few years. I believe I have 6 or 8 of them and usually start a slot with a razor saw and follow with the appropriate StewMac file. These shorten the time it takes to slot the nut and increase the accuracy and cleanliness of the job. When I do not have the correct file size I use the next thinner and finish the job with folded sandpaper.

Gauged Nut Slotting Files

I have a bunch of them. If you need to make a slot for E1 0.9 string, no worries, just buy 0.010" slotting file and GENTLY polish it along one edge from both sides (so that you will still have 0.010" edge) using a flat piece of fine-grit abrasive paper (I used 600 followed by 1200), and keep measuring with a caliper - BINGO.

Best available, but could be even better

I am not a professional luthier, but I have purchased every size of these files and used them extensively to experiment with the setup on my acoustic guitars. The good:1) The setup has a huge impact on the quality of sound from a guitar. Using accurate tools such as these can achieve that sound.2) The large number of gauges can be a bit expensive, but it is the only option for getting a tight fitting (and hence no buzzing) slot. This set offers most (see below) of the required gauges.What could be improved:1) The markings on the files easily rub off. I read this in another review and immediately wrapped mine in scotch tape, which solved the problem.2) The 0.010" file is flimsy and difficult to use. It should have a stiffener added.3) I double checked the gauges of the files with a micrometer. They are mostly accurate, except for the narrowest guages like 0.010 and 0.013, which have a (acceptably) small variation across the length of the file.4) And the easiest to fix: I think there is a gauge missing. Most gauges are spaced 0.003" or 0.004" apart with the exception 0.035"-0.042" and 0.050"-0.056". In my opinion, this spacings are too wide. Stewmac says that the file can be rocked to change the size of the slot, but note that this is a one-sided maneuver. It can only change the width of the slot in one direction. If you needed a 0.041" slot you would have to use the 0.035" file and "rock" it wider by 0.;006" and hope that you did not go too far. This is very difficult to do.